A soon as it was realized that asbestos should no longer be used in its many applications, materials scientists innovated and developed replacement materials. That's why I had non-asbestos insulated gloves, made from ceramicfiber, in my laboratory in the 1980s.

For the present study, the research team assembled a database of 73,000 patents for energy-related technologies in more than a hundred countries in the period 1970-2008. Energy-related patents were identified by keyword search, not by the classification assigned by the various patent offices. A recent surge in patents appeared in many renewable energy technologies.[2]

The number of solar energy patents increased by 13% annually between 2004 and 2009; and the number of wind energy patents increased 19% annually. For comparison, the annual growth rate approached or exceeded that for similar high-tech areas, such as digital communications and semiconductor devices. There were fewer than 200 renewable energy patent issued per year in the United States from 1975-2000, but this increased to more than a thousand annually by 2009. Even fossil fuel patents showed an uptick (see graph).[1]

The trend in energy patents from 1974-2008 shows rapid growth in the last decade.

China has been faulted for merely commercializing technologies invented elsewhere, and being successful through innovation only in production processes. The PLoS ONE study, however, shows a dramatic recent growth in the number of renewable-energy technology patents filed in China.[2] Although the number includes filings by entities outside China, the idea that companies feel a need for such defensive patents indicates their belief that China will be a future player in this technology area.